Abstract

This paper describes a 2 month study of the patterns of abundance, feeding pressure, diet and feeding selectivity in corallivorous tubelip wrasses (Labridae), rarely studied, yet widespread and abundant group of corallivores on Indo-Pacific coral reefs. The relative abundance and feeding pressure of corallivorous wrasses and butterflyfishes (Chaetodontidae) in Kimbe Bay, Papua New Guinea, were compared. Overall, tubelip wrasses were more than twice as abundant as corallivorous butterflyfishes and accounted for three times as many feeding bites on corals. The three most abundant tubelip wrasses (yellowtail tubelip Diproctacanthus xanthurus, Allen's tubelip Labropsis alleni and the tubelip wrasse Labrichthys unilineatus) were all obligate corallivores taking > 97% of bites from the surface of live corals. Labropsis alleni and D. xanthurus were highly selective, consuming preferred prey species in proportions significantly higher than expected given their availability. In contrast, L. unilineatus was fairly non-selective and consumed most corals in direct accordance with their availability. As coral predators, tubelip wrasses are highly comparable to coral-feeding butterflyfishes in the coral species consumed, range of dietary specialization and their reliance on live coral. Tubelip wrasses, however, may supersede butterflyfishes as the predominant corallivorous family in some Indo-Pacific locations, and coral-feeding tubelip wrasses are likely to be severely affected by coral decline.